Kenya's Vincent Kipchumba (L), Kenya's Eliud Kipchoge (C) and Kenya's Benson Kipruto (R) lead the elite men's race of the 2020 London Marathon in central London on October 4, 2020.[AP]

It's billed as the 42km contest of the season, with a start list brimming with menace, speed, endurance and athletic power.

With Kelvin Kiptum, the world's second fastest marathoner in history, defending champion Benson Kipruto, Los Angeles Marathon winner John Korir, 2019 world marathon champion Ruth Chepng'etich and 2021 London Marathon winner Joyceline Jepkosgei; the 45th Chicago Marathon battle on Sunnday promises a hair-raising action.

In this mix of gunpowder, there are 2018 Commonwealth Games 10,000m silver medallist Stacy Ndiwa, half marathon specialist Daniel Mateiko and Wesley Kiptoo.

Others include Belgium's Olympic bronze medallist Bashir Abdi (2:03:36), Ethiopians Dawit Wolde (2:04:27), Seifu Tura (2:04:29) and USA's Galen Rupp (2:06:07).

Kipruto, who trains with 2022 London Marathon winner Amos Kipruto at 2Running Club near Kapsabet, has a leg up against his challengers-having mastered the pan-cake Chicago Marathon course that has 31 turns. The race starts and ends at the famous Grant Park.

He must be at his best to counter Kiptum (2:01.25) and Korir (2:05.01).

Kipruto said: "I know the battle will not be easy. If at all the pace will be fast, it will be to my advantage because I long to improve on my personal best.

"There is nothing as good as hanging on with the leading pack in a marathon competition. You have to make thorough calculations during the race," said Kipruto.

Not bad for an athlete who has competed in 13 marathons and won four races which include Toronto Marathon in 2018 (2:07:24) and Prague Marathon in 2021 (2:10:16).

In 2021, Kipruto chalked up victory at the Boston Marathon in 2:09.51 and proceeded to win Chicago Marathon last year in 2:04.24.

He returned to Boston Marathon last April and wound up third, where Evans Chebet won the race.

Should Kipruto win, he will be the first back-to-back men's champion since the late Olympic champion Sammy Wanjiru in 2010.

Mateiko looks excited to make his marathon debut in Chicago.

Mateiko, who has been competing in track and half marathons, vowed to pull a surprise in the American race.

"Yes, this is my first time to run a marathon and a major one. This means I have to work extra hard to keep up with the high pace," he said.

Mateiko banks on the experience he gathered as a pacesetter at the London Marathon last April where Kiptum won.

He said: "I had good pacing at the London marathon where I did it up to 30km."

Mateiko has a rich CV in 21km contests: winner at the inaugural Eldama Ravine Half Marathon, runner up at the Ras Al Khaimah Half Marathon, third at the Copenhagen Half Marathon (59.27) and a 58.26 personal best mark set at the Valencia Half Marathon.

In the women's front, Los Angeles Marathon winner Stacy Jepkemoi Ndiwa returns to American soil against a classy line up.

She will be up against defending champion Ruth Chepng'etich and Jepkosgei.

Ndiwa, an alumnus of Kosirai Girls High School in Nandi County and a former Africa 10,000m champion, said: "

"This will be my first time to compete in world majors but I am ready to square it out with the top marathoners in the world," said Ndiwa.

After making her debut last year when she finished 4th at the Istanbul marathon in 2:31.53, the Mount Elgon born runner in Bungoma County went ahead to win the Los Angeles marathon on March 19th this year in 2:31.00.

"This will be my third marathon after recording good times in Istanbul and Los Angeles. It will be my time to showcase my talent in road running after track," she said.

In May, Ndiwa won the second edition of the Iten 15km Road race and went ahead to finish second at the Boston 10km in 31:25 behind Hellen Obiri (32:21).

"This will be an avenue for me to enter into the big league of marathon running. Competing at the World Majors Marathon is not a walk in the park but hard work will pay out," she said.